If confirmed, the astonishing claim would upend a cardinal rule of physics established by Albert Einstein nearly a century ago.

"Most theorists believe that nothing can travel faster than the speed of light. So if this is true, it would rock the foundations of physics," said Stephen Parke, head of the theoretical physics department at the U.S. government-run Fermilab near Chicago, Illinois.

The team shot neutrinos out of a particle accelerator near Geneva, Switzerland, and measured how long it took the particles to travel to a neutrino detector in Gran Sasso, Italy, 450 miles (724 kilometers) away.

According to Goldberg's calculations, if neutrinos travel faster than light by the amount the OPERA team claims, then neutrinos from that supernova should have been detected in 1984—three years before the photons.

"It's possible, but unlikely," Goldberg said, that detectors active on Earth at the time would have missed such an obvious spike in cosmic neutrinos.

Goldberg concedes that supernova neutrinos are less energetic—and would thus be traveling slower—than the neutrinos from CERN's particle accelerator.

However, "assuming Einstein was correct, both types [of neutrinos] would be moving at something like 99.999999999 percent the speed of light," Goldberg said in an email.

"In other words, from a measurement point of view, they'd be going at essentially identical speeds."

Even if the OPERA results are confirmed by other scientists, they wouldn't totally invalidate Einstein's theories of general and special relativity, Stanford University's Strigari stressed. Those theories still explain a remarkable range of observed phenomena in the universe.

"I think it's long been understood that the theories we have today aren't the full answers," Strigari said.

"If this observation holds up, then it's probably a good piece of evidence that the theories we currently have need to be reworked."